Details of Disappearance
Pehringer was last seen at her Riverton, Wyoming home on April 17, 1989. She disappeared while her fourteen-year-old daughter was at school. She took her purse and glasses with her, but her vehicle was left behind.
When Pehringer's daughter came home from school, her mother was gone and there was no note to explain her absence, which was uncharacteristic of her behavior. She has never been heard from again. Her loved ones described her as a responsible and punctual woman who had been taking classes at Central Wyoming College.
Authorities believe Pehringer left her residence willingly with someone she knew, and intended to be gone for only a short time. There was no sign of a struggle of her house after she vanished, but several cigarette butts were found; some were of Pehringer's preferred brand, but a few were from a brand she didn't smoke.
After her disappearance, her daughter found her diary and gave it to the police. According to the diary, Pehringer had been dating Donald Kenneth Pack Jr., who had been paroled from prison a few years earlier.
Pack had served a twelve- to fourteen-year sentence for for aggravated rape and kidnapping, and was a suspect in more than 30 rapes in the Jackson, Wyoming area. His preferred victim was a single or divorced woman in her mid-thirties, slightly overweight and of below average to average height, a description that matched Pehringer.
Psychologists who profiled Pack said he was very intelligent and very dangerous and would probably kill his next victim to keep her from reporting the attack. However, authorities were never able to tie him to Pehringer's disappearance.
About a year after she went missing, Pack's parole was revoked after he was arrested on weapons charges and he spent another year in prison before being released again. In 2018, Pack was sentenced to eight to twelve years in prison after some old evidence was located and tested for DNA, tying him to two unsolved rapes.
Authorities believe Pehringer was the victim of a homicide. Her case remains unsolved.